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2013

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Articles 361 - 390 of 541

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Habitat Characterization, Distribution, And Areal Extent Of Deep-Sea Coral Ecosystems Off Florida, Southeastern U.S.A., John K. Reed, Charles G. Messing, Brian K. Walker, Sandra Brooke, Thiago B.S. Correa, Myra Brouwer, Tina Udouj, Stephanie Farrington Jan 2013

Habitat Characterization, Distribution, And Areal Extent Of Deep-Sea Coral Ecosystems Off Florida, Southeastern U.S.A., John K. Reed, Charles G. Messing, Brian K. Walker, Sandra Brooke, Thiago B.S. Correa, Myra Brouwer, Tina Udouj, Stephanie Farrington

Marine & Environmental Sciences Faculty Articles

The deep-sea (200-1000 m) seafloor off the southeastern U.S. has a variety of extensive deep-sea coral ecosystem (DSCE) habitats including: deep-water coral mounds; various hard-bottom habitats off Florida including the Miami Terrace, Pourtales Terrace, and deep-water canyons (Agassiz and Tortugas Valleys); and deep island slopes off western Bahamas and northern Cuba. The dominant structure-forming scleractinian corals are Lophelia pertusa and Enallopsammia profunda; other structure-forming taxa include stylasterid corals, gorgonians, black corals, and sponges. This biota is associated with hard-bottom seafloor of variable high-relief topography which can be remotely identified from bathymetric data. NOAA bathymetric contour maps and digital elevation …


The Global Sustainability Transition: It Is More Than Changing Light Bulbs, Michael P. Weinstein, R. Eugene Turner, Carles Ibanez Jan 2013

The Global Sustainability Transition: It Is More Than Changing Light Bulbs, Michael P. Weinstein, R. Eugene Turner, Carles Ibanez

Faculty Publications

Current policies and norms to reconcile human demands for resources with the Earth’s ability to supply them have resulted in practices that mainly treat the symptoms of unsustainability rather than their underlying causes. Moreover, the increase in our knowledge about humankind’s role in ecosystems is not keeping pace with our understanding of the consequences of our actions, resulting in a deepening inability to address sustainability issues. The extreme complexity and intricate workings of the world require the expansion of our mental models in a systems-thinking framework if we are to realize a sustainable place for humans in it. The challenge …


High-Latitude Short-Period Mesospheric Gravity Wave Dynamics And Winter Climatology, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland Jan 2013

High-Latitude Short-Period Mesospheric Gravity Wave Dynamics And Winter Climatology, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland

Physics Student Research

Short-period gravity wave observations over the Arctic region are few and their impact on the Arctic mesosphere lower thermosphere region via momentum deposition is of high interest. The Mesospheric Airglow Imaging and Dynamics project was initiated in January 2011 to investigate the presence and dynamics of these waves over the interior of Alaska. Observations were made from Poker Flat Research Range (PFRR) using an all-sky imager. This site provides an exceptional opportunity to establish a long-term climatology of short-period gravity waves in the Arctic Region. We present summary measurements of prominent gravity waves over two consecutive winters and compare their …


Reconstruction Of Family-Level Phylogenetic Relationships Within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes, Malcolm S. Hill, April L. Hill, Jose V. Lopez, Kevin J. Peterson, Shirley Pomponi, Maria C. Diaz, Robert W. Thacker, Maja Adamska, Nicole Boury-Esnault, Paco Cárdenas, Andia Chaves-Fonnegra, Elizabeth Danka, Bre-Onna De Laine, Dawn Formica, Eduardo Hajdu, Gisele Lobo-Hajdu, Sarah Klontz, Christine C. Morrow, Jignasa Patel, Bernard Picton, Davide Pisani, Deborah Pohlmann, Niamh E. Redmond, John Reed, Stacy Richey, Ana Riesgo, Ewelina Rubin, Zach Russell, Klaus Rützler, Erik A. Sperling, Michael Di Stefano, James E. Tarver, Allen G. Collins Jan 2013

Reconstruction Of Family-Level Phylogenetic Relationships Within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes, Malcolm S. Hill, April L. Hill, Jose V. Lopez, Kevin J. Peterson, Shirley Pomponi, Maria C. Diaz, Robert W. Thacker, Maja Adamska, Nicole Boury-Esnault, Paco Cárdenas, Andia Chaves-Fonnegra, Elizabeth Danka, Bre-Onna De Laine, Dawn Formica, Eduardo Hajdu, Gisele Lobo-Hajdu, Sarah Klontz, Christine C. Morrow, Jignasa Patel, Bernard Picton, Davide Pisani, Deborah Pohlmann, Niamh E. Redmond, John Reed, Stacy Richey, Ana Riesgo, Ewelina Rubin, Zach Russell, Klaus Rützler, Erik A. Sperling, Michael Di Stefano, James E. Tarver, Allen G. Collins

Marine & Environmental Sciences Faculty Articles

Background: Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges.

Methodology/Principal Findings: We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha), but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosap, …


Evaluating Acropora Cervicornis Growth And Survivorship In A Line Nursery, Zachary Ostroff Jan 2013

Evaluating Acropora Cervicornis Growth And Survivorship In A Line Nursery, Zachary Ostroff

HCNSO Student Theses and Dissertations

Acropora cervicornis and A. palmata were once dominant, reef-building corals of Caribbean reefs. Over the last several decades, population declines of Caribbean Acropora have been dramatic, and both species are now listed as “Threatened” under the United States Endangered Species Act. Numerous restoration efforts now utilize coral gardening techniques to cultivate these species for transplantation, in which A. cervicornis is primarily cultivated both on fixed structures and in line nurseries. This study evaluates growth and survivorship of multiple A. cervicornis genotypes grown via two line nursery techniques, and compares the efficacy of each against the conventional method of fixed nursery …


Occurrence Of Antimicrobials And Antimicrobial Resistance Genes In Beef Cattle Storage Ponds And Swine Treatment Lagoons, Yuping Zhang, Chiqian Zhang, David B. Parker, Daniel D. Snow, Zhi Zhou, Xu Li Jan 2013

Occurrence Of Antimicrobials And Antimicrobial Resistance Genes In Beef Cattle Storage Ponds And Swine Treatment Lagoons, Yuping Zhang, Chiqian Zhang, David B. Parker, Daniel D. Snow, Zhi Zhou, Xu Li

Nebraska Water Center: Faculty Publications

Livestock manure treatment and storage structures are potential environmental sources of antimicrobials and antimicrobial resistance genes (ARGs). In this study, the occurrence of antimicrobials and ARGs was investigated in the water and the sludge compartments of beef cattle storage ponds and swine lagoons. Analysis was focused on two families of antimicrobials (sulfonamide and tetracycline) and the corresponding ARGs (sul1, sul2, tetO, tetQ and tetX). Results showed that the pseudo-partitioning coefficients of tetracyclines were higher than those of sulfonamides, suggesting different distributions of these two classes of antimicrobials between water and sludge. The ARGs tested were …


Spectral Characterization Of The Nigerian Shoreline Using Landsat Imagery, Olumide Fadahunsi, Shachak Pe'eri, Christopher Parrish, Andy Armstrong, Lee Alexander Jan 2013

Spectral Characterization Of The Nigerian Shoreline Using Landsat Imagery, Olumide Fadahunsi, Shachak Pe'eri, Christopher Parrish, Andy Armstrong, Lee Alexander

Center for Coastal and Ocean Mapping

The challenges of shoreline mapping include the high costs of acquiring up-to-date survey data over the coastal area. As a result, in many developing countries, the shoreline has not been consistently mapped. The variety of methods used for this mapping and the large time differences between the surveys (on the order of decades) could result in inaccuracies in shoreline data. This study presents the development of a shoreline characterization procedure for the Nigerian coastline using satellite remote sensing technology. The study goal is to produce a complete, consistent and continuous shoreline map using publicly available data processed in a GIS …


Observations Of The Vertical Structure Of Tidal Currents In Two Inlets, Thomas C. Lippmann, James D. Irish, Jonathan Hunt Jan 2013

Observations Of The Vertical Structure Of Tidal Currents In Two Inlets, Thomas C. Lippmann, James D. Irish, Jonathan Hunt

Center for Coastal and Ocean Mapping

Observations of the vertical structure of broad band tidal currents were obtained at two energetic inlets. Each experiment took place over a 4 week period, the first at Hampton Inlet in southeastern New Hampshire, USA, in the Fall of 2011, and the second at New River Inlet in southern North Carolina, USA, in the spring of 2012. The temporal variation and vertical structure of the currents were observed at each site with 600 kHz and 1200 kHz RDI Acoustic Doppler Current Profilers (ADCP) deployed on low-profile bottom tripods in 7.5 and 12.5 m water depths near the entrance to Hampton …


Bathymetric Terrain Model Of The Atlantic Margin For Marine Geological Investigations., Brian Andrews, Jason D. Chaytor, Uri S. Ten Brink, Daniel S. Brothers, James V. Gardner Jan 2013

Bathymetric Terrain Model Of The Atlantic Margin For Marine Geological Investigations., Brian Andrews, Jason D. Chaytor, Uri S. Ten Brink, Daniel S. Brothers, James V. Gardner

Center for Coastal and Ocean Mapping

Bathymetric terrain models of seafloor morphology are an important component of marine geological investigations. Advances in acquisition and processing technologies of bathymetric data have facilitated the creation of high-resolution bathymetric surfaces that approach the resolution of similar surfaces available for onshore investigations. These bathymetric terrain models provide a detailed representation of the Earth’s subaqueous surface and, when combined with other geophysical and geological datasets, allow for interpretation of modern and ancient geological processes. The purpose of the bathymetric terrain model presented in this report is to provide a high-quality bathymetric surface of the Atlantic margin of the United States that …


Long-Term (1951-2007) Rainfall Trends Around Six Indian Cities: Current State, Meteorological, And Urban Dynamics, Shailesh Kumar Kharol, D. G. Kaskaoutis, Anu Rani Sharma, Ramesh P. Singh Jan 2013

Long-Term (1951-2007) Rainfall Trends Around Six Indian Cities: Current State, Meteorological, And Urban Dynamics, Shailesh Kumar Kharol, D. G. Kaskaoutis, Anu Rani Sharma, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

The present study focuses on analyzing the precipitation trends over six Indian cities during the summer monsoon (June-September) covering the period 1951-2007 and also attempting to investigate possible urban forcing and dynamics by examining the variation in precipitation in the upwind and downwind directions. The analysis shows negative trends in the total number of rainy days over Hyderabad (-10.4%), Kanpur (-7.1%), Jaipur (-10.5%), and Nagpur (-4.8%) and positive trends over Delhi (7.4%) and Bangalore (22.9%). On the other hand, decreases of -21.3%, -5.9%, -14.2%, and -14.6% in seasonal rainfall are found over Delhi, Hyderabad, Jaipur, and Kanpur, respectively, whereas Bangalore …


Critical Research Needs For Successful Food Systems Adaptation To Climate Change, Michelle Miller, Molly Anderson, Charles A. Francis, Chad Kruger, Carol Barford, Jacob Park, Brent H. Mccown Jan 2013

Critical Research Needs For Successful Food Systems Adaptation To Climate Change, Michelle Miller, Molly Anderson, Charles A. Francis, Chad Kruger, Carol Barford, Jacob Park, Brent H. Mccown

Department of Agronomy and Horticulture: Faculty Publications

There is a growing sense of the fragility of agricultural production in the Global North and South and of increasing risks to food security, as scientific observations confirm significant changes in the Gulf Stream, polar ice, atmospheric CO2, methane release, and other measures of climate change. This sense is heightened as each of us experiences extreme weather, such as the increasing frequency of droughts, floods, unseasonal temperatures, and erratic seasonality. The central research challenge before us is how global, national, regional, and local food systems may adapt to accelerating climate change stresses and uncertainties to ensure the availability, …


Climate Change: What Does It Mean For Nebraska?, Martha D. Shulski, Natalie A. Umphlett, Tapan B. Pathak, Kenneth G. Hubbard Jan 2013

Climate Change: What Does It Mean For Nebraska?, Martha D. Shulski, Natalie A. Umphlett, Tapan B. Pathak, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

Because Nebraska’s location on the North American continent is far removed from large bodies of water, Nebraskans experience a strong continental type climate. As such, residents do not benefit from the moderating influence of the ocean, and temperatures can have wide swings from day to day and season to season. Typical characteristics for a continental climate at this latitude are large temperature variability with warm summers dominated by convective thunderstorms, and cold winters influenced by snow and wind from mid-latitude cyclones.


Water Quality Assessment Of Sager Creek Utilizing Physiochemical Parameters And A Family-Level Biotic Index, T. S. Wakefield Jan 2013

Water Quality Assessment Of Sager Creek Utilizing Physiochemical Parameters And A Family-Level Biotic Index, T. S. Wakefield

Journal of the Arkansas Academy of Science

An annual rapid bioassessment and physiochemical survey of Sager Creek in Northwest Arkansas was conducted. Sager Creek is a first to second order stream that flows through the city of Siloam Springs, AR. Invertebrate collections and water samples were collected at three different reaches, with the most downstream reach being below the effluent of the Siloam Springs Wastewater Treatment Plant. Benthic arthropods were collected, identified, and counted to produce a family-level biotic index and a family-level index of diversity. Statistical analysis revealed that these indices were significantly different for the effluent- influenced reach. However, this difference could not be correlated …


Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer Jan 2013

Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer

Electronic Theses and Dissertations

Sagebrush (Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances continue to alter this ecosystem, with climate change possibly representing the greatest future disturbance risk. Improved ways to characterize and monitor gradual change in this ecosystem are vital to its future management. A new remote sensing sagebrush characterization approach was developed in Wyoming which integrates three scales of remote sensing to derive four primary continuous field components (bare ground, herbaceousness, litter, and shrub), and four secondary components (sagebrush, big sagebrush, Wyoming sagebrush, and shrub …


Water Column Variability In A Coastal Tourist Cave In Mallorca, Spain, Liana M. Boop, Bogdan P. Onac, Jonathan G. Wynn, Joan J. Fornós, Marta Rodríguez-Homar Jan 2013

Water Column Variability In A Coastal Tourist Cave In Mallorca, Spain, Liana M. Boop, Bogdan P. Onac, Jonathan G. Wynn, Joan J. Fornós, Marta Rodríguez-Homar

National Cave and Karst Management Symposium 2013

Coves del Drac is visited by more than 1 million tourists annually and has been a tourist destination in the western Mediterranean for over 100 years. All areas of the cave are developed with historic or current tour route infrastructure, including walkways, handrails, and electric lighting. This study compares one vertical water profile collected along the current tour path with two other profiles from historic tour route locations. Differences in freshwater and organic inputs, as well as direct anthropogenic impacts, are clearly observed in the aquatic parameters and stable isotopes collected in the profiles. Anthropogenically-driven undersaturation in the cave pools, …


Vibrio Parahaemolyticus Interactions With Chitin In Response To Environmental Factors, Vanessa Molina Jan 2013

Vibrio Parahaemolyticus Interactions With Chitin In Response To Environmental Factors, Vanessa Molina

LSU Doctoral Dissertations

Vibrio parahaemolyticus is a naturally occurring chitinoclastic human pathogen that adsorbs to substrates, including chitinous copepods and oysters, as part of its ecology, a phenomenon that is important in its responses to changes in environmental factors such as temperature and salinity. Little is known about acute responses of V. parahaemolyticus when subjected to abrupt environmental changes such as those encountered during postharvest oyster treatments such as icing, exposure to mammalian host conditions, and transport via ballast water. The following in vitro studies investigated V. parahaemolyticus adsorption and gene expression as a function of substrate, temperature, and salinity as a model …


Degradable Plastics And Solid Waste Management Systems, David J. Tonjes, Krista L. Thyberg Jan 2013

Degradable Plastics And Solid Waste Management Systems, David J. Tonjes, Krista L. Thyberg

Technology & Society Faculty Publications

Plastics, which are woven into the fabric of modern life, have consequential impacts on the environment. Many of these are associated with end-of-lifetime processes, and include chemical contamination of the environment and effects from litter. Plastics also complicate waste management processes, causing contamination in composting operations, and having poor recovery rates through recycling. Plastics that are not as biologically recalcitrant, that decompose when use is done, have been perceived as solutions to at least some of these problems. The first generation of degradable plastics did not meet marketing claims; some of the more recent formulations, partly as a consequence of …


Arsenic And Phosphorus Biogeochemistry In The Ocean: Arsenic Species As Proxies For P-Limitation, Oliver Wurl, Louise Zimmer, Gregory A. Cutter Jan 2013

Arsenic And Phosphorus Biogeochemistry In The Ocean: Arsenic Species As Proxies For P-Limitation, Oliver Wurl, Louise Zimmer, Gregory A. Cutter

OES Faculty Publications

Arsenic and phosphorus are biochemically very similar, and hence arsenate (As5+) is toxic by interfering with the energy metabolism, in particular during P limitation. However, many phytoplankton detoxify As by reducing arsenate to arsenite (As3+), and/or methylating it to mono and dimethyl As. Such As detoxification becomes operative in oligotrophic waters when phosphate concentrations are below those for As; therefore, we evaluated the potential use of these detoxification products as indicators of P-limitation by measuring As speciation during the US GEOTRACES North Atlantic transect. The distribution of As3+ concentrations in surface waters is similar to …


Intercalibraton In Chemical Oceanography-- Getting The Right Number, Gregory A. Cutter Jan 2013

Intercalibraton In Chemical Oceanography-- Getting The Right Number, Gregory A. Cutter

OES Faculty Publications

Intercalibration has a strict metrological definition, but in brief, it's an open sharing of methods and results between laboratories to achieve the most accurate data with the fewest random and systematic errors. In the field of chemical oceanography where concentrations of many constituents can be in the nano- to picomolar range, the salt water matrix can be difficult to analyze, and knowing the exact concentrations, or even chemical forms, of biologically required elements is essential, intercalibration is a very relevant and needed tool. Implementing it is not simple because errors can occur at any step in the process of taking …


Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan Jan 2013

Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan

OES Faculty Publications

Dissolved inorganic phosphorus (DIP) concentrations in surface water of vast areas of the ocean are extremely low (<10 nM) and phosphorus (P) availability could limit primary productivity in these regions. We explore the use of oxygen isotopic signature of dissolved phosphate (δ18OPO4) to investigate biogeochemical cycling of P in the Sargasso Sea, Atlantic Ocean. Additional techniques for studying P dynamics including 33P-based DIP turnover time estimates and percent of cells expressing alkaline phosphatase (AP) activity as measured by enzyme-labeling fluorescence are also used. In surface waters, δ18OPO4 values were lower than equilibrium by 3–6%, indicative of dissolved organic phosphorous (DOP) remineralization by extracellular enzymes. An isotope mass balance model using a variety of possible combinations of …


Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada Jan 2013

Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada

OES Faculty Publications

In many continental margin Sediments, a deep reaction zone exists which is separated from remineralization processes near the sediment surface. Here, methane diffuses upward to a depth where it is oxidized by downwardly diffusing sulfate. However, the methane sources that drive this anaerobic oxidation of methane (AOM) in the sulfate-methane transition zone (SMT) may vary among sites. In particular, these sources can be thought of as either (i) "internal" sources from in situ methanogenesis (regardless of where it occurs in the sediment column) that are ultimately coupled to organic matter deposition and burial, or (ii) "external" sources such as hydrocarbon …


Surface Production Fuels Deep Heterotrophic Respiration In Northern Peatlands, J. Elizabeth Corbett, David J. Burdige, Malak M. Tfaily, Angela R. Dial, William T. Cooper, Paul H. Glaser, Jeffrey P. Chanton Jan 2013

Surface Production Fuels Deep Heterotrophic Respiration In Northern Peatlands, J. Elizabeth Corbett, David J. Burdige, Malak M. Tfaily, Angela R. Dial, William T. Cooper, Paul H. Glaser, Jeffrey P. Chanton

OES Faculty Publications

Multiple analyses of dissolved organic carbon (DOC) from pore waters were conducted to define the processes that govern carbon balance in peatlands: (1) source, reactivity, and transport of DOC with respect to vegetation, peat, and age of carbon substrate, (2) reactivity of DOC with respect to molecular size, and (3) lability to photoxidation of surficial DOC. We found that surface organic production fuels heterotrophic respiration at depth in advection-dominated peatlands, especially in fens. Fen DOC was Δ14Cenriched relative to the surrounding fen peat, and fen respiration products were similar to this enriched DOC indicating that DOC was the …


Diatom Proteomics Reveals Unique Acclimation Strategies To Mitigate Fe Limitation, Brook L. Nunn, Jessica F. Faux, Anna A. Hippman, Maria T. Maldonado, H. Rodger Harvey, David R. Goodlett, Philip W. Boyd, Robert F. Strzepek Jan 2013

Diatom Proteomics Reveals Unique Acclimation Strategies To Mitigate Fe Limitation, Brook L. Nunn, Jessica F. Faux, Anna A. Hippman, Maria T. Maldonado, H. Rodger Harvey, David R. Goodlett, Philip W. Boyd, Robert F. Strzepek

OES Faculty Publications

Phytoplankton growth rates are limited by the supply of iron (Fe) in approximately one third of the open ocean, with major implications for carbon dioxide sequestration and carbon (C) biogeochemistry. To date, understanding how alteration of Fe supply changes phytoplankton physiology has focused on traditional metrics such as growth rate, elemental composition, and biophysical measurements such as photosynthetic competence (Fv/Fm). Researchers have subsequently employed transcriptomics to probe relationships between changes in Fe supply and phytoplankton physiology. Recently, studies have investigated longer-term (i.e. following acclimation) responses of phytoplankton to various Fe conditions. In the present study, the coastal diatom, Thalassiosira pseudonana, …


Dinitrogen Fixation In Aphotic Oxygenated Marine Environments, Eyal Rahav, Edo Bar-Zeev, Sarah Ohayon, Hila Elifantz, Natalia Belkin, Barak Herut, Margaret R. Mulholland, Iiana Berman-Frank Jan 2013

Dinitrogen Fixation In Aphotic Oxygenated Marine Environments, Eyal Rahav, Edo Bar-Zeev, Sarah Ohayon, Hila Elifantz, Natalia Belkin, Barak Herut, Margaret R. Mulholland, Iiana Berman-Frank

OES Faculty Publications

We measured N2 fixation rates from oceanic zones that have traditionally been ignored as sources of biological N2fixation; the aphotic, fully oxygenated, nitrate (NO¯3)-rich, waters of the oligotrophic Levantine Basin (LB) and the Gulf of Aqaba (GA). N2 fixation rates measured from pelagic aphotic waters to depths up to 720 m, during the mixed and stratified periods, ranged from 0.01 nmol N L-1 d-1 to 0.38 nmol N L-1 d-1. N2 fixation rates correlated significantly with bacterial productivity and heterotrophic diazotrophs were identified from aphotic as well as …


Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones Jan 2013

Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones

OES Faculty Publications

Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …


Distributions Of Particulate Heme B In The Atlantic And Southern Oceans- Implications For Electron Transport In Phytoplankton, Martha Gledhill, Eric P. Achterberg, David J. Honey, Maria C. Nielsdottir, Micha J.A. Rijkenberg Jan 2013

Distributions Of Particulate Heme B In The Atlantic And Southern Oceans- Implications For Electron Transport In Phytoplankton, Martha Gledhill, Eric P. Achterberg, David J. Honey, Maria C. Nielsdottir, Micha J.A. Rijkenberg

OES Faculty Publications

Concentrations of heme b, the iron-containing component of b-type hemoproteins, ranged from b concentrations were enhanced in the photic zone and decreased with depth. Heme b concentrations correlated positively with chlorophyll a (chl a) in the TNA (r=0.41, pb did not correlate with chl a in the IB or SS. In the IB and SS, stations with high-chlorophyll and low-nutrient (Fe and/or Si) concentrations exhibited low heme bconcentrations relative to particulate organic carbon (< 0.1 μmolmol-1, and high chl a:heme b ratios (> 500). High chl a:heme b ratios resulted from relative decreases in …


Combined Effects Of Co2 And Light On Large And Small Isolates Of The Unicellular N2-Fixing Cyanobacterium Crocosphaera Watsonii From The Western Tropical Atlantic Ocean, Nathan S. Garcia, Fei-Xue Fu, Cynthia L. Breene, Elizabeth K. Yu, Peter W. Bernhardt, Margaret R. Mulholland, David A. Hutchins Jan 2013

Combined Effects Of Co2 And Light On Large And Small Isolates Of The Unicellular N2-Fixing Cyanobacterium Crocosphaera Watsonii From The Western Tropical Atlantic Ocean, Nathan S. Garcia, Fei-Xue Fu, Cynthia L. Breene, Elizabeth K. Yu, Peter W. Bernhardt, Margaret R. Mulholland, David A. Hutchins

OES Faculty Publications

We examined the combined effects of light and pCO2 on growth, CO2-fixation and N2-fixation rates by strains of the unicellular marine N2-fixing cyanobacterium Crocosphaera watsonii with small (WH0401) and large (WH0402) cells that were isolated from the western tropical Atlantic Ocean. In low-pCO2-acclimated cultures (190ppm) of WH0401, growth, CO2-fixation and N2-fixation rates were significantly lower than those in cultures acclimated to higher (present-day approximate to 385ppm, or future approximate to 750ppm) pCO2 treatments. Growth rates were not significantly different, however, in low-pCO2-acclimated cultures of …


Development And Deployment Of A Point-Source Digital Inline Holographic Microscope For The Study Of Plankton And Particles To A Depth Of 6000 M, Alexander B. Bochdansky, Manfred H. Jericho, Gerhard J. Herndl Jan 2013

Development And Deployment Of A Point-Source Digital Inline Holographic Microscope For The Study Of Plankton And Particles To A Depth Of 6000 M, Alexander B. Bochdansky, Manfred H. Jericho, Gerhard J. Herndl

OES Faculty Publications

Bochdansky, A. B., Jericho, M. H., & Herndl, G. J. (2013). Development and deployment of a point-source digital inline holographic microscope for the study of plankton and particles to a depth of 6000 m. Limnology and Oceanography: Methods, 11, 28-40. doi: 10.4319/lom.2013.11.28


Hci And Cio Profiles Inside The Antarctic Vortex As Observed By Smiles In November 2009: Comparisons With Mls And Ace-Fts Instruments, T. Sugita, Y. Kasai, Y. Terao, S. Hayashida, G. L. Manney, W. H. Daffer, H. Sagawa, M. Suzuki, M. Shiotani, K. A. Walker, C. D. Boone, P. F. Bernath Jan 2013

Hci And Cio Profiles Inside The Antarctic Vortex As Observed By Smiles In November 2009: Comparisons With Mls And Ace-Fts Instruments, T. Sugita, Y. Kasai, Y. Terao, S. Hayashida, G. L. Manney, W. H. Daffer, H. Sagawa, M. Suzuki, M. Shiotani, K. A. Walker, C. D. Boone, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We present vertical profiles of hydrogen chloride (HCl) and chlorine monoxide (ClO) as observed by the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on the International Space Station (ISS) inside the Antarctic vortex on 19-24 November 2009. The SMILES HCl value reveals 2.8-3.1 ppbv between 450K and 500K levels in potential temperature (PT). The high value of HCl is highlighted since it is suggested that HCl is a main component of the total inorganic chlorine Cly, defined as Cly similar or equal to HCl + ClO + chlorine nitrate ClONO2, inside the Antarctic vortex in spring, owing …


Stratospheric Loss And Atmospheric Lifetimes Of Cfc-11 And Cfc-12 Derived From Satellite Observations, K. Minschwaner, L. Hoffmann, A. Brown, M. Riese, R. Müller, P. F. Bernath Jan 2013

Stratospheric Loss And Atmospheric Lifetimes Of Cfc-11 And Cfc-12 Derived From Satellite Observations, K. Minschwaner, L. Hoffmann, A. Brown, M. Riese, R. Müller, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

The lifetimes of CFC-11 and CFC-12 have been evaluated using global observations of their stratospheric distributions from satellite-based instruments over the time period from 1992 to 2010. The chlorofluorocarbon (CFC) datasets are from the Cryogen Limb Array Etalon Spectrometer (CLAES), the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA-1 and CRISTA-2), the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), and the Atmospheric Chemistry Experiment (ACE). Stratospheric loss rates were calculated using an ultraviolet radiative transfer code with updated cross section and solar irradiance data. Mean steady-state lifetimes based on these observations are 44.7 (36-58) yr for CFC-11 and 106.6 …